Standoff insulator



Dec. 19, 1950 K. ERIKSEN Erm. Re. 23,310

STAND-OFF INSULATOR Original Filed Feb. 14, 1948 INVENTOR. KENNETHERIKSEN CARL W.CONCELMAN Ewig/W4@ ATTOR NEY Reuued Dec. 19, 1950STANDOFF INSULATOR Kenneth Eriksen and Carl W. Concehnan, Brookield,Conn., assignors to Hazeltine Research, Inc., Chicago, Ill., acorporation of Illinois Original No. 2,476,407, dated July 19, 1949,Serial No. 8,414, February 14, 1948. Application for reissue July 15,1950, Serial No. 173,964

Matter enclosed in heavy brackets appears in the original patent butforms no part o! tllls reissue speelilcation: matter printed in italicsindicates the additions made by reissue Claims.

The present invention relates to stand-off insulators and, particularly,to such insulators adapted to support an antenna in spaced relation to aconductive surface, such as the body of an automobile.

Stand-oi! insulators heretofore proposed for mounting antennas on thinrigid surfaces, such as the top or side of an automobile, have requiredthe use of an excessively complex construction involving an unduly largenumber of structural components. They have thus been not only undulyexpensive to manufacture but also have been expensive to install sincethey require an excessive installation time. When the antenna is mountedon the top or side of an automobile, the previously proposedarrangements have frequently made it necessary to mutilate a significantportion of an inner protective and decorative fabric, particularly whenthe antenna is mounted on the top of the automobile.

It is an object of the present invention, therefore, to providea new andimproved stand-off insulator which avoids one or more of thedisadvantages and limitations of prior such insulators.

It is a further object oi the invention to provide a stand-off insulatorwhich is very simple in construction and is easily, readily and quicklyinstalled with both a minimum of effort and of the number of toolsrequired.

It is an additional object of the invention to provide a new andimproved stand-off insulator which when mounted on a ground plane may beinstalled from one side only thereof.

It is still an additional object of the invention to provide, in anantenna installation for a vehicle, a stand-off insulator having a novelsecuring means.

IIt is yet another object of the invention to provide a stand-oilinsulator which employs a minimum number of simple and inexpensiveelectrical and mechanical parts In accordance with the invention, astand-off insulator for supporting an antenna in insulated spacedrelation to the surface of a conductive member [of sheet material]comprises an externally threaded mounting structure which includes aprojecting portion provided [adjacent one end thereof] with [a pluralityof peripherally] spaced latch elements. These latch elements are[transversely] movable to permit the r insertion of the one end of theprojecting portion through an aperture in the conductive member andthereafter to latch the projecting portion in the aperture. Thestand-oirinsulator also comprises a [insulator] structure which includes 2 A[means for securing the insulator structure to the mounting structure.One of these structures includes] a member threaded onto the threadedmounting structure for clamping the conductive member between the latchelements and the lastmentioned member. One of the aforesaid structuresof the stand-of insulator includes means for supporting the antenna ininsulated spaced relation to the conductive member. [The standoffinsulator further includes means for supporting the antenna from theinsulator structure] For a better understanding of the presentinvention, together with other and further objects thereof, reference ishad to the following description taken in connection with theaccompanying drawing, and. its scope will be pointed out in the appendedclaims.

In the drawing, Fig. l is an elevational view partially in cross sectionshowing a stand-oi! insulator embodying the invention; Fig. 2 is adetail view of a sleeve element utilized in the insulator arrangement;and Fig. 3 illustrates a slightly modiiied form of the presentinvention.

Referring now more particularly to Fig. i of the drawing, the stand-odinsulator is utilized to support an antenna Il in insulated spacedrelation to the surface of a conductive member I2 of sheet materialwhich may, for example, be the top of an automobile. A coaxialtransmission line I3 leading from a wave-signal apparatus, not shown. iscoupled to the antenna Il. The insulator arrangement comprises amounting structure I4 which includes a hollow cylindrical metal sleevel5, the constructional i'eatures of which a-re more clearly apparentfrom Fig. 2 of the drawing, having on one end thereof a collar Il offrusto-eonical coniiguration. The sleeve I5 with its collar I1 islongitudinally slotted.` over the major portion of its length to providea plurality of circumferentially spaced resilient iingers I8. Theslotted segments of the collar, l! thus provide on the remote end ofeach of the iingers I8 is wedge-shaped latch element I9 with a shoulder20 facing the other end of the sleeve. The ilngers I8 are resilientlymovable transversely of a longitudinal axis common to the fingers topermit the insertion of the ngers I9 through an aperture 2l provided inthe conductive sheet member i2. An externally vthreaded sleeve member 22is press iitted over that end of the sleeve l5 which is remote from thelatch elements I9.

The stand-of! insulator also includes a hollow insulator structure 23having means for securing the insulator structure 23 tothe mountingstructure Il. The means last mentionedmay. for example, compriseinternal threads 24 provided on a dome-shaped insulator I. One of thestructures Il and 23 includes means movable along a longitudinal axis ofthe mounting structure Il for causing the latch elements I9 firmly tosecurerthe projecting portion of the mounting structure including thefingersv I8 thereof in the aperture 2|. In the arrangement disclosed,the means last mentioned is a part of the mounting structure Il andcomprises a clamping member 25 internally and externally threaded, thismember being threaded onto'the sleeve member 22 to clamp the conductivemember I2 between the shoulders 20 of the latch elements I9 and theclamping member 25. The elements 22 and 25 Y each have provision madefor holding them with a wrench in order that the member 25 may besuitably tightened down. The mounting structure Il also includes ahollow sleeve member 26, which is insertable into the hollow projectingportion of the sleeve I after the insertion of this portion within theaperture 2|, to restrain the latch elements I9 against furthertransverse movement.

The transmission line I3. extends through the sleeve I5 of the mountingstructure I4 and an internally threaded and apertured conductive capmember 21 is threaded onto the sleeve member 22 'of the mountingstructure mechanically to clamp and electrically to connect the outerconductor 2l of the coaxial transmission line I3 to the mountingstructure.

The internally threaded insulator I is threaded onto the clampingmem-ber 25 to secure the insulatorstructure 23 to the mounting structureIl.

y The coaxial transmission line I3 has an inner conductor 29 whichextends through the apertured cap 21 in insulated relation therewith.Means, comprising a coupling structure 33, is provided for supportingthe antenna |I on the insulator structure 23 and'for electricallyconnecting the inner conductor 29 of the transmission line to theantenna. 'I'he coupling structure 33 comprises a inner conductive sleeve3| which is secured within an axial aperture 32 of the insulator I. Thesleeve 3| has a flange 33 at one end to engage the interior surface ofthe insulator I and a flange 3l intermediate its ends to engage theexterior` surface of the insulator I. An outer end of the sleeve 3|carries a threaded portion 35 for receiving an internally threadedconductive cap vmember 36 which is integral with theV antenna Il andsecures the latter to the coupling structure 30. The sleeve 3| isradially slotted to receive the bent-over end of the transmission-lineinner conductor 23 and also has an external circumferential groove atthis end so that the end of the conductor 29 can be wound around to liein this groove and thereby be securely clamped between the sleeve 3| andcap member 36. The coupling structure 30 thus not only serves to supporttheantenna I I on the insulator structure 23, but also serveselectrically to connect the inner conductor 29 of the transmission lineI3 to the antenna II.

.The mounting structure I4 preferably includes a metallic washer 31interposed between the clamping member v25 and the upper side of theconductive member I2. A rubber gasket 38 preferably is interposedbetween the broad base of the insulator I and the top surface oftheconductive member I2 to provide a watertight joint therebetween. y

The method of assembly of the stand-oil insulator is best described bystar-ting with the mounting structure I4'. The hole 2| is first drilledor otherwise formed, in the, conductive member I2. After assembling thewasher 31 on the end of the metal sleeve I5, the latter is then insertedintorthe.l hole 2| suiliciently far that the shoulders 20 of\the latchelements I1 engage. the underside of the member I2. The sleeve member 26is next forced downwardly into the sleeve I5 to prevent further inwardilex'ing of the flexible lingers I3. The clamping member 25 is nowthreaded onto the externally threaded member 22 rmly to clamp theshoulders 20 of the latching element I1 against the underside of theconductive member I2. Then the coaxial transmission line I3 is preparedfor insertion upwardly within the sleeve 25, the outer conductor 28 ofthe transmission line being bent outwardly over the top portions of theelements IB, 22, and 26. The inner conductor 29, with its insulationthereon, is now inserted through the aperture of the cap 21 and thelatter is threaded into the member 22 to.clamp the line outer conductor23 to the mounting structure Il.

After positioning the rubber gasket 33 and inserting the inner conductor29 of the transmission line through the sleeve 3| of the couplingstructure 30, the insulator structure 23 is next screwed onto the member25 and tightened down against the member I2. The internal conductor 29is next wound around the groove in the end of the sleeve 3| and the cap35 is screwed onto the portion 35 of the latter to complete theassembly.

Thenovel stand-oil insulator described provides a rigid construction forsupporting an antenna in insulated spaced relation to the surface of aconductive member,'ensures a positive electrical connection between theexternal conductor ofa coaxial cable and the conductive member,

and further ensures a positive electrical connection between the innerconductor of the transmission line and the antenna. All the parts of`the assembly are simple in construction, easily installed and readilyreplaceable. The broadbase insulator structure 23 provides amplerigidity for the antenna II in a transverse direction.

Two stand-olf insulators having substantially the construction abovedescribed may be utilized to support a vertical antenna in insulatedspaced relation to the side 39o! an automobile as shown in Fig. 3.elements of Fig. 3, which correspond to similar elements of Fig. 1 beingdesignated by the. same reference numerals. In the instant arrangement,the coupling structure 30 is formed with a transverse bore III and asetscrew 4I may be used to hold the antenna I I in a fixed positionrelative to the insulator structure 23.

It will be apparent from the above description of the invention that astand-oil' insulator embodying the invention has the advantage that itis possible to mount an antenna on a conductive surface by operationsperformed from one side only of the latter. Such installation requires aminimum number of simple tools and can be accomplished in a very shortperiod oi time by an unskilled person. The stand-oi! insulator of thepresent invention has the additional advantage that it not only providesa very rigid mounting for an antenna but one which may be readilywaterproofed. Further, positive and secure electrical connectionsbetween an associated transmission line and both the antenna and itssupporting conductlvesurface member are assured.

casio The stand-oil insulator is simple in construction and involvesonly a comparatively few inexpensive components easily manufactured lnquantity.

While there have been described what are at present considered to be thepreferred embodiments of this invention, it will be obvious to thoseskilled in the art that various changes and modiflcations may be madetherein without departing from the invention, and it is, therefore,aimed to cover all such vchanges and modifications as fall within thetrue spirit and scope of the invention.

Whatisclaimedis:

l. A stand-off insulator for supporting an antenna in insulated spacedrelation to the surface of a conductive member of sheet materialcomprising, a mounting structure including a projecting portion providedadjacent one end thereof with a plurality of peripherally spaced latchelements transversely movable to permit the insertion of said one end ofsaid projecting portion through an aperture in said conductive memberand thereafter to latch said projecting portion in said aperture, eachof said latch eiements including a wedge-shaped portion having ashoulder facing the other end of said projecting portion, said structureincluding longitudinally movable means for clamping said conductivemember between said means and the shoulders of said latch elements, andan insulator structure including means for attachment to said mountingstructure, and means for supporting said antenna from said insulatorstructure.

2. A stand-oil insulator for supporting an antenna in insulated spacedrelation to the surface of a conductive member of sheet materialcomprising, a mounting structure including a sleeve longitudinallyslotted at one end thereof and having at said one end a longitudinallyslotted collar of frusto-conical configuration to provide a plurality ofcrcumferentially spaced resilient nngers each having on said one rendthereof a wedge-shaped latch element with a shoulder portion facing theother end of said sleeve' and movable transversely to permit theinsertion of said fingers in an aperture of said conductive member andthereafter to latch said fingers in said aperture, an insulatorstructure including means for attachment to said mounting structure, oneof said structuresincluding means for causing said latch elements rmlyto secure said fingers in said aperture, and means for supporting saidantenna from said insulator structure.

3. A stand-olf insulator for supporting an antenna in insulated spacedrelation to the surface of a conductive member of sheet materialcomprising, an externally threaded mounting structure including aprojecting portion provided adjacent one end thereof with a plurality ofperipherally spaced latch elements transversely movable to permit theinsertion of said one end oi' said projecting portion through anaperture in said conductive member yan thereafter to latch saidprojecting portion in said aperture, an insulator structure includingmeans for attachment to said mounting structure, one of said structuresincluding a member threaded onto said threaded mounting structure forclamping said conductive member between said latch elements and saidlast-mentioned member, and means for supporting said antenna from saidinsulator structure.

4. A stand-oi! insulator for supporting an antenna in insulated spacedrelation to the surface of a conductive member of sheet materia-lcomprising, an externally threaded mounting structure including aprojecting portion provided adjacent one end thereof with a plurality ofperipherally spaced latch elements transversely movable to permit theinsertion of said one end of said projecting portion through an aperturein said conductive member and thereafter to latch said projectingportion in said aperture, said mounting structure including anexternally and internally threaded clamping member threaded onto saidthreaded portion of said mounting structure for clamping said conductivemember between said latch elements and said last-mentioned member, aninternally threaded insulator structure threaded onto said clampingmember for attachment to said mounting structure, and means forsupporting said antenna from said insulator structure.

5. A stand-off insulator for supporting an antenna in insulated spacedrelation to the surface of a conductive member, and for coupling acoaxial transmission line to said antenna, comprising: an externallythreaded, hollow, conductive, mounting structure including a hollow pro-`iecting portion provided adjacent one end thereof with a plurality ofperipherally spaced latch elements transversely movable to permit theinsertion of said one end of said projecting portion through an aperturein said conductive member and thereafter to latch said projectingportion in said aperture; said structure including an externally andinternally threaded clamping member threaded onto said mountingstructure for clamping said conductive member between said latchelements and said clamping member; an internally threaded insulatorstructure threaded onto said clamping member for attachment to e saidmounting structure; an internally threaded and apertured conductive capmember threaded onto said clamping member and adapted electrically andmechanically to connect to said mounting structure the outer conductorof a coaxial transmission line which extends through said hollow portionthereof; said transmission line having an inner conductor extendingthrough said apertured cap in insulated relation therewith; and meansfor supporting said antenna von said insulator structure and for elec-.trically connecting said inner conductor to said antenna.

6. AV stand-off insulator for supporting an antenna in insulated spacedrelation to the surface of a conductive member comprising: an externallythreaded mounting structure including a projecting portion provided withspaced latch elements movable to permit the insertion of said projectingportion through an aperture in said conductive member and thereafter tolatch said projecting portion in said aperture; and a structureincluding a member threaded onto said threaded mounting structure forclamping said conductive member between said latch elements and saidlast-mentioned member; one of said structures including means forsupporting said antenna in insulated spaced relation to said conductivemember.

7. A stand-op' insulator for supporting an antenna in insulated spacedrelation to the surface of a. conductive member comprising: anexternally threaded mounting structure including a projecting portionprovided with a plurality of peripherally spaced latch elementsmovableto permit the insertion of said projecting portion through anaperture in said conductive member and thereaperture; and a structureincluding a memberv threaded onto said threaded mounting structure lorclamping said conductive member between said latch elements and saidlast-mentioned member; one of said-structures including means forsupporting said antenna in insulated spaced relation to said conductivemember.

8.' A stand-og' insulator for supporting an antenna in insulated spacedrelation to the surface of a conductive member comprising: an externallythreaded mounting structure including a Proiecting portion provided withspaced latch elements movable to permit the insertion of said projectingportion through an aperture in said conductive member and thereafter tolatch said projecting portion in said aperture; a structure including amember threaded o nto said threaded mounting structure for clamping saidconductive member between said latch elements and said last-mentionedmember; and an internally 'threaded and apertured conductive cap memberthreaded onto said mounting structure and adapted electrically andmechanically to connect to said mounting structure the outer conductorof a coaxial transmission line which extends through said mountingstructure; said secondmentioned structure including means for supportingsaid antenna in insulated spaced relation to said conductive member andincluding means for electrically connecting the inner conductor of saidtransmission line to said antenna. 9. A stand-017 insulator forsupporting an antenna in insulated spaced relation to the surface of aconductive member comprising: an externally threaded hollow mountingstructure including a projecting portion provided with a plurality ofperipherally spaced latch elements movable to permit the insertion ofsaid projecting portion through an aperture in said conductive memberand thereafter to latch said projecting portion in 'said aperture; aninsulator structure including a member threaded onto said threadedmounting structure for clamping said conductive member l said mountingstructure and adapted electrically and mechanically to connect to saidstructure the outer conductor of a coaxial transmission line whichextends through said mounting structure; said insulator structureincluding means for supporting thereon said antenna in insulated spacedrelation to said conductive menibe'r and for electrically connecting theinner conductor of said transmission line to said antenna.

10. A stand-og' insulator for supporting an antenna in insulated spacedrelation to the surface of a conductive member comprising: an ezternallythreaded hollow mountingvstructure in cluding a protecting portionprovided with spaced latch elements movable to permit the insertion ofsaid projecting portion through an aperture in said conductive memberand thereafter to latch said projecting portion in said aperture; aninsulator structure including a member threaded onto said threadedmounting structure for clamping said conductive member between saidlatch elements and said last-mentioned member; and

REFERENCES CITED l The following references are of record in the tile ofthis patent:

UNITED STATES PATENTS Number Name Date 1,910,226 Austin May 23. 19332,219,327 Miller Oct. 29, 1940 2,420,826y Ingang May 20, 1947 2,424,804De Swart July 27. 1947 Bryers -c Jan. 20, 1948

